Rear Caliper seals are slightly wrong size

[showaddydadito]

In my experience this weekend, it's true about the aftermarket rear caliper dust seals being the wrong spec.

I bought new seals for front and back calipers. For the front I got genuine Yam parts, but got aftermarket for the back (because that's what Wemoto had in stock). ('96 Diversion 600)

On the back - the dust seals are too deep a profile from the inner edge to the outer. So when you put them in and try to put the piston in it is almost impossible to get the piston in without turning the seal over when the piston goes in.

This would result in the dust seal being bnggered, and possibly in it pulling down into the fluid seal too.

I have a steady eye, nerves of steel, a scalpel, and a piece of Arkansas stone - I also have a need to use the bike to get to work on Monday morning - so I took about .3mm off the outside diameter of the seal, which then worked a treat.

Moral of story - be careful.

I have written to Wemoto. I'm sure they trade these items in good faith, but if no one tells them they'll never know.

[General Gman]

In my not-very-humble opinion, dust seals are mostly pointless so I remove them anyway...

[showaddydadito]

Oh - bum - you mean all that was a wast of time?

[sparky392]

I had similar prob with seals for my rear caliper, after hours of trying to get pistons back in i phoned wemoto to ask if there were a problem with seals, to which they said not heard of any, but when they checked part number on the packet they sent me it turned out they had sent wrong seals. I received correct seals next day and pistons just slipped in without effort, they didn't even ask for old ones back.

[ukd4v1d]

i had same problem with fronts, i bought seal set off ebay, the hydraulic seals were perfect but the dust seal for the small pots of both sides were too big (as in too thick to fit in the grove)

[amorti]

I've used pattern rear seals from Bike Business in Portsmouth and they were fine.